main seal leak

J

jerkyjohn

Junior Member
I 've had my "31" coupe for about 5 years now. It was purchased without much history and only has about 5200 miles on what I believe to be a "29" engine. Was restored in the late 80's, early 90's and sat in a garage until 2006.
It developed a main seal oil leak in spring 2019.
Does anyone know if there is anything that can be done without pulling the engine?
I read a couple of articles in the Technically Speaking manuals about some possible solutions by dropping the oil pan and making some simple changes to the main cap, or by reducing the size of the oil feeder tube. These articles are somewhat dated, and of coarse the authors of these articles are no longer around.
Has anyone tried these remedies?
 
Rear seal and oil level is good. Don't know about shaft play. I'm not that mechanical and just wondering about these other solutions that I read about. I am having difficulty finding someone to do the work. everyone assumes engine has to be pulled
 
Am I'm reading your posts correctly and your leak is at the front of the engine?
If so it might not be your front seal leaking but could be oil getting past the right front motor mount bolt as it goes into the crank case. Often it will make it look like a front seal leak. Simple fix if it is.
 
so many things can leak,some of which are normal.
the rear main,
-wash the area clean from oil and dry it
-inspect with a flash light the rear pan area, see if the gaskets especially the rear cork is it in properly.
- clean the shop floor and dry it.
- start it up and let it run for 1/2 hr on a slight high idle.
- shut it off and with your flash light see if oil is on the floor.
- look at the back of the engine to see if the oil can be traced to a specific spot.
next
if it didn't leak at an idle take a 5 mile drive at road speed.
- park it on your clean shop floor
- watch where it leaks from
- if it leaks after the run pull off your oil filler cap and make sure there is no obstruction in the fill tube or cap, the engine needs to vent to the atmosphere and that needs to be clear. if it is plugged , take off the tube and clean it out. if someone has put a nonvented cap on the engine get the correct cap. drive the car again and see what happens.
if it is not plugged keep looking.
- if it is coming out of a cork gasket. the pan needs to come off and at that point you can check the rear main drain tube and the orifice that goes into the rear main, needs to be clear.
-if oil is dripping out from the cotter pin hole the leak may be the rear main.
- the bad news is that if the rear main has too much clearance then that could also be the source of the leak and the mains need to be re-shimmed, the rear is not that easy to do with the engine in the car.
- end play the crank needs endplay but not much you can check end play by using a bar to gently pry the crank ahead then push it back. by the front pulley or remove the throwout bearing cover of the bell housing which is easier you can push on the clutch pedal and then pry the flywheel back with a big screwdriver. the end play spec is only .003" but i have seen up to .030". if the endplay is excessive it may create a leak if so then the engine has to come out to fix.

the centre main will leak if it has the wrong shims but that should be easy to see, the oil will be running down the block just behind the oil fill tube. if thats where it is leaking the pan has to come off and proper shims installed.

the front main. is just a goose turd, the one on the pan is easy to replace with the pan off. the top one then the crank needs to come down to get it replaced .

this will start you off. it is never the easy repair

ou
 
Check your oil breath. What weight oil are you using?

How much oil is it leaving when parked?
 
one more idea on tracing the leak, if the oil is running down between the bell housing and engine block it may not have a gasket in there. the end of the camshaft journal exits the block there and oil will leak out if there is no gasket.
the engine needs to come out to fix that.
ou
 
Thanks guys, but you didn't read the question.
Is anyone familiar with "Technically Speaking" manuals; A compilation of articles originally published in the Model "A" News? There are some articles regarding potentially easy fixes of leaking rear seal that can be made without removing the engine. Instead by dropping the oil pan, pulling the main cap, cutting an oil groove, and drilling drain hole. Or another article talks about reducing the size of the oil feeder tube.
Has anyone ever heard of, or done these repairs to stop a rear main seal leak?
 
jerkyjohn said:
Thanks guys, but you didn't read the question.
Is anyone familiar with "Technically Speaking" manuals; A compilation of articles originally published in the Model "A" News? There are some articles regarding potentially easy fixes of leaking rear seal that can be made without removing the engine. Instead by dropping the oil pan, pulling the main cap, cutting an oil groove, and drilling drain hole. Or another article talks about reducing the size of the oil feeder tube.
Has anyone ever heard of, or done these repairs to stop a rear main seal leak?
Click to expand...

I don’t think you are reading the answers. You got good info from knowledgeable and experienced guys telling you how to identify where the leak is coming from. No one can say it’s not a bad rear main or you don’t have to remove the engine without having the data they are seeking. If the data show the problem is the rear main, the best way to determine that for certain is either drop the pan or pull the engine. The hard truth is there is no good easy solution for a bad rear main that leaks.
 
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Here is one attempt I found on engine I bought--- it didn't work ,drilled in the wrong place, the traditional "fix" was to cut a groove near the rear thrust flange with a drain hole at the bottom , the idea being to reduce oil getting to rear thrust flange.
This was described to me when I was at the auto auction by old time used car guys , ones that knew all the old time coverup fixes to slow down leakers ----I got a good education on how to shim insert bearings ,quiet noisey rears and where to poke the hole to move the odometer wheel
 

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Thank you Kurt, that was an answer I was Looking for. I read the articles and just wonder if indeed these quick fixes work.
 
jerkyjohn said:
Thanks guys, but you didn't read the question.
Is anyone familiar with "Technically Speaking" manuals; A compilation of articles originally published in the Model "A" News? There are some articles regarding potentially easy fixes of leaking rear seal that can be made without removing the engine. Instead by dropping the oil pan, pulling the main cap, cutting an oil groove, and drilling drain hole. Or another article talks about reducing the size of the oil feeder tube.
Has anyone ever heard of, or done these repairs to stop a rear main seal leak?
Click to expand...

a quick fix will work if the quick fix is focused on the situation that is causing the leak. you may know where the oil Apears to be coming from but you must not know what is causing the leak or you would know how to fix it.

it would appear to me that the fix that Kurt in NJ just shows he has the engine out of the car.

and you better know the cause or you can spend hours pulling the motor, putting it back together and still have a leaky motor

ou
 
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the engine as it came from ford new was not leak free,it had drips. but oil did not run out.
put the engine into the condition that the ford manuals suggest and the engine will function as normal.
my opinion is home made invented fixes such as shown with the main drilled to stop oil from getting to the thrust surfaces are not a fix at all. these sort of things may cause more engine problems in the long run.
good luck with your project

ou
 
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jerkyjohn said:
It developed a main seal oil leak in spring 2019.
Click to expand...

In post #4 you said: "Rear seal and oil level is good."

You still haven't admitted if the leak is at the front main or the rear main, which is it front or rear?

How much does it leak?
 
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